The present invention relates generally to mobile lift-assisted transport devices. More specifically, the present invention relates to a mobile lift-assisted transport device which is able to easily be elevated and lowered through the use of pneumatic powering means.
A busy Emergency Medical Services (EMS) crew may handle as many as 20 calls during the work shift. Typically one or more such calls involve moving a patient from a field location, such as his home or the scene of an accident, to a health care facility such as an emergency room at a hospital.
Providing transport for the patient involves various procedures for appropriately securing the patient in different transport vehicles for transport to the hospital or other appropriate destination. Such transport involves a constant risk to the EMS crew and to the patient. The risk arises from the activity involving the EMS crew, usually two persons, lifting and moving the patients. There is also the danger that the patient may be dropped or roughly handled while being moved. As for the EMS crew, they are routinely faced with lifting situations which can and often do result in significant and even crippling back injuries. This can occur either because of the repetitive lifting of average size patients or occasional lifting of large patients.
The dangers of lifting-related injury is compounded because an EMS crew must lift a patient approximately 7 times during the course of a call. For example, for lifting purposes only, in an emergency involving a 200 lb. man the crew must: 1) lift the patient to a mobile, wheeled device placed at its lowest height adjustment; 2) lift the device and patient to the maximum height adjustment, and then move the device and patient to an ambulance; 3) lower the device and patient back to the lowest height adjustment; 4) lift the device and patient into the ambulance; 5) upon arrival at the medical facility, remove the device and patient from the ambulance and lower them to the ground; 6) again, lift the device and patient to the maximum height adjustment, and then move the device and patient into the facility; and 7) lift to transfer the patient from the device to a bed at the facility. During this very typical call the crew has lifted or lowered the patient seven times, thereby doing an amount of work equivalent to lifting more than 1400 pounds when the weight of the device is included.
A particularly difficult part of this process results from the fact that the typical device that is used in the field, e.g., a stretcher for transfer of patients via ambulances, is not well-designed for lifting and lowering. Because of the location of the undercarriage and supporting structure, the members of the EMS crew cannot simply stand on each side of the device and lift or lower it using proper lifting techniques with their legs. Rather, to avoid hitting the undercarriage with their knees, they must turn their bodies sideways, imposing a torquing motion on their backs as they lift and lower. This consequence results in a significant number of disabling back injuries to EMS personnel each year. In addition, because of the strength that is required to lift and lower a device with this type of motion, smaller people, particularly women, are effectively precluded from working as emergency medical technicians.
The foregoing illustrates that it would be advantageous to provide a patient transport device having a lift assisting mechanism, to overcome the need for an EMS crew to exert a great amount of lifting force during a routine emergency call.
Although several such transport devices have been proposed, all are too cumbersome to be practically implemented. One example of such a device is found in U.S. Pat. No. 2,833,587 to Saunders which discloses an adjustable height gurney which includes power cylinders provided in the legs of the upper frame and connected to two of the intersecting lever arms (one on each side of the gurney). To operate the cylinders, the EMS technician repeatedly works the handle of a grip up and down to actuate the hydraulic pump. As an alternative, a valve connects the power cylinders to the fluid reservoir, which valve may be opened by a hand lever connected thereto. Both mechanisms for actuating the hydraulic pump cause problems in operation. Use of the handle, which requires repeatedly working the handle up and down is time consuming and be quite difficult when a patient is on a gurney. Further, in order to remove the gurney from the ambulance, or to place it in the ambulance, the EMS technicians must lift the stretcher, and the patient, from the ambulance to the ground, and visa versa. Then the technicians can use the grip or hand lever to raise the upper carriage. the gurney in the Saunders patent does not provide a means for raising and lowering the lower carriage, in addition to raising and lowering the upper carriage.
The present invention provides a novel lift-assisted device for transporting objects or patients from one location to another. The present invention allows the lift-assisted apparatus to easily be raised and lowered through pneumatic powering means so that the user has to use little force or energy.
The present invention provides a novel lift-assisted device which is able to lift and lower heavy loads while enduring the stress and strains caused by the heavy loads.
The present invention provides a novel lift-assisted device wherein the powering means is easily accessible, reasonably priced and may easily be replaced.
The present invention provides the above advantages, amongst others, by providing a lift-assisted device having a seat portion, a seat support portion which supports the seat portion, a base portion, an undercarriage portion which comprises of at least one scissor linkage member, each scissor linkage member including a first member pivotable connected to a second member near a center portion of the first and second member, a pneumatic bag located between the seat portion and the base portion, a pneumatic cylinder located between the seat portion and the base portion, a pneumatic powering means for powering the pneumatic bag and/or pneumatic cylinder, and wherein the first member and second member are slidably connected to the seat portion on one end and fixedly connected to the base portion on an opposite end.